450 CHARACTERS OF SEA-LIONS CHAP. Fain. 1. Otariidae.—The family Otariidae l is no doubt the least modified of the aquatic Caraivora. It is rational, therefore to commence the survey of the group with this family. They have preserved, as already noted, the independence of the hind* limbs; the external ear is present, though small; there is an obvious neck, and the nostrils are at the end of the snout, as in FIG. 229.—Cape Sea-Lion. Otaricc, pusiXla. x ^. terrestrial creatures generally. The nails are small and rudi- mentary, save those upon the three middle digits of the foot. It is a singular fact that among the Otaries the angle of the lower jaw is "inflected as much as in any Marsupial/* The literature relating to this family is great, and it seems difficult to reconcile the very varying opinions as to how many genera ought to be adnutted. Mr. Allen arranged the nine species which he allowed 1 See especially Allen, North American Pinnipcdes, 1880.